In the past, multilayer interconnects have been made increasingly finer as semiconductor devices have become more highly integrated. Japanese Laid-Open Patent 218,028/93 is a publicly known example relating to multilayer interconnects. There are many such examples in which normally, as shown in FIG. 6, an insulating film such as silicon oxide film 28 is used between the bottom layer metal interconnect lines.
In many such conventional multiple layer interconnect structures, the dielectric constant of silicon oxide film 28a is approximately 4, so that capacitance has been increasing between interconnect lines in recent devices, in which spacing between bottom layer metal interconnect lines 20 is becoming less than 1 micron as integration increases, causing undesirable phenomena such as degraded circuit operating speeds. The need has therefore arisen to use insulating materials with a low dielectric constant as an inter-layer insulating film. When these are applied to fine interconnects, however, a low viscosity precursor has to be used, since the [space] between the fine interconnect lines is filled, and a laminate structure is necessary for use with an inter-layer insulating film requiring a prescribed film thickness. There are problems, however, such as the occurrence of peeling at the time of multiple layering, difficulty in coating the precursor, etc.